Cultivating a truly North Fork beer through wild yeast

Ian Van Bourgondien, right, and Pete Barraud in the North Fork Brewing Company building in Riverhead. (Credit: David Benthal)

On a recent outing, Southold native Ian Van Bourgondien plucked a beach plum from along the shores of the Peconic Bay. The fruit, or more specifically the naturally growing yeast on its surface, is now at the foundation of one of North Fork Brewing Company’s small-batch beers.

The Riverhead brewery, which Van Bourgondien recently opened with his cousin and brewer Pete Barraud of Baiting Hollow, is harnessing the power of wild fermentation — a centuries-old, yet rarely utilized, technique that captures local terroir in a pint.

Wild yeast beers are comparable to wines in the sense that the taste of each batch relies on the characteristics of the environment. The beach plum, like a grape grown at a local vineyard, is inherently different from one grown elsewhere due to factors like soil and climate.

Van Bourgondien is using his background in biology to coax out pure strains of yeast from locally grown beach plums, blackberries and other fruits for beers that are distinct to this region. The brewery also locally sources its grains and hops, which Barraud and Van Bourgondien grow at their farm in Peconic.

“I can write a recipe for a standard American pale ale and put standard domesticated yeast into it and it will taste like a pale ale, but then I could do the same recipe and use a huckleberry wild yeast and you’ll get more tart characters,” Barraud said. “The esters in it set it apart. We can put the same strain of wild yeast into different beer styles and it’s going to change differently.”

Wild yeast is all around us. There are organisms in the air, in the dust, on the surface of fruits — and they are often the same species of domesticated yeast that’s normally used to ferment beer.

“It’s like the difference between a wolf and a dog,” Van Bourgondien explained. “Dogs are domesticated and we can predict their behavior. They evolved with us, whereas a wolf is wild and you can’t predict its behavior, but if you go back far enough, they are the same species.”

The most notable difference between domesticated yeast and wild yeast is that its recipe can be replicated in large, consistent quantities. It’s the reason many brewers shy away from the process and why North Fork Brewing’s flagship beer uses a domesticated strain.

This wild yeast was cultivated from a North Fork beach plum. (Credit: David Benthal)

“It’s a style a lot of brewers want to do, but are nervous about, because of the risk involved,” said Barraud, who previously brewed with Moustache Brewing Co. in Riverhead. “There’s a lot of unpredictability with wild yeast. What you’ll end up with is not what you intended it to be.”

Van Bourgondien’s process of isolating individual strains helps curb the risk and ensures the beer can be replicated in small amounts. It’s a modern take on a traditional Belgian way of brewing, where open vats of unfermented beer would be left in orchards to collect the naturally occurring yeasts and bacteria in the air.

That old-school style of spontaneous fermentation is alive and well and being done locally by none other than the North Fork’s OG. Pat Alfred was tasked with implementing a barrel program when he signed on as head brewer at Greenport Harbor Brewing Co. two years ago. In his tenure, he’s rolled out the popular OG “Original Greenport” series, a self-described “calculated experimentation” using old- and new-school methods of brewing.

Alfred’s latest experimentation is the North Fork Ales series. The collection of beers are being created entirely from locally grown ingredients, from the barley to the hops and, yes, the yeast. The first North Fork Native Ale was born right before Christmas.

A small tank of unfermented Greenport Harbor beer wort was left uncovered overnight at Mattebella Vineyards in Southold, where it captured local yeast and bacteria. The next morning it was collected and transferred into two Raphael Vineyards merlot barrels to ferment. The sour beer is still sitting in the brewery’s Greenport location — only time will tell when or if it will be ready to taste.

“Knowing when it’s ready to serve is such a hard question to answer,” said Alfred, who previously worked at Barrier Brewing in Oceanside. “This is not a temperature-controlled room, wood breathes, it depends on the content of the barrel before — all these things are factors in the fermentation.”

Ian Van Bourgondien works to isolate individual strains of yeast in the brewery’s lab. (Credit: David Benthal)

There are more than 10 spontaneously fermented beers lying in wait. All are mixed fermentations, some containing upwards of 20 different strains of yeast and bacteria all working together. One strain dies, gets eaten by another and so on, in turn creating a unique flavor profile.

“My approach to this style of beermaking is Old World,” he said. “It’s sensory, developing flavors naturally. These types of wild yeast beers have been around for centuries. They were just having fun saying, ‘This works, this doesn’t work, let’s blend this with that.’ It’s more like being a chef.”

Alfred’s goal is to make a batch at multiple North Fork wineries and eventually blend and release them in small batches at the brewery’s tasting rooms and at specialty beer shops.

“It’s such a slow process,” he noted. “These barrels, for all I know, will need to be dumped. That’s why I want to continue to do this because at some point something will stick and we’ll be able to harness the yeast we want or we’ll have a process that we can lock into so we can continually make good spontaneously fermented beer. It will become the house culture.”

Barraud and Van Bourgondien are also re-collecting their wild yeast strains for future use.

After the fermentation process, the beer is chilled to 30 degrees. At that point, the yeast goes into hibernation and falls to the bottom of the tank. Barraud then harvests the yeast into kegs after it settles and prior to the carbonation process. The yeast can be reused 12 to 20 times before it’s exhausted and the strain must be retired.

“Then you just say good night and make some more wild yeast,” Barraud said.